Multi-section variable density mattress

ABSTRACT

A mattress possessing particular utility in hospitals and nursing homes reduces the incidence and severity of bed sores, improves muscle tone and reduces back ache. The mattress features plural sections of foam whose densities and degrees of compressibility vary, so that regulated pressures will be applied to different sections of the body for maximum comfort. The mattress may be turned to change the pressure points on the body periodically as the need arises. The mattress is employed in conjunction with a foam padded base or underlay having a relatively rigid component.

United States Patent 1191 Weinstock 1 Nov.'12, 1974 1 MULTI-SECTIONVARIABLE DENSITY MATTRESS lnventor: Clifford Weinstock, Pompano Beach,Fla.

Neurological Research and Development Group Incorporated, Scranton, Pa.

Filed: Mar. 28, 1973 Appl. No.: 345,605

Related U.S. Application Data Continuation-in-part of Ser. No. 233,687,March 10, 1972, abandonedv [73] Assignee:

U.S. Cl. 5/345 R, 5/91, 5/355, 5/D1G; 2

Int. Cl A47c 27/08, A470 27/22 Field of Search 5/91, 345, 355, DIG. 2;297/457, DlG. l, DIG. 2

References Cited UNITED STATESPATENTS 1/1969 Maddax et a1. 5/91 mxnksmasgrt aaaaas A? 3.447.170 6/1969 Spitz 5/91 3,521,311 3/1968 Cohen..v5/D1G. 2 3,604,025 9/1971 Mims 5/345 FOREIGN PATENTS OR APPLICATIONS1,553,658 1/1969 France 5/345 R Primary Examiner-Casmir A. Nunberg [57]ABSTRACT 5 Claims, 5 Drawing Figures MULTI-SECTION VARIABLE DENSITYMATTRESS I This application is a continuation inpart of application Ser.No. 233,687 filed on the 10th day of March, 1972, now abandoned.

BACKGROUND OF THE INVENTION A definite need exists for an improved bedmattress particularly in hospitals and nursing homes where some patientsare confined to the bed for long periods of time. Also in the home,certain individuals with chronic back complaints experience the need fora mattress which would tend to ease such complaints.

The prior art contains quite a number of teachings pertaining tosectional mattresses and mattresses having variable density compoentsbut none of these prior art structures has proven to be completelysatisfactory in terms of satisfying the above needs of bedriddenhospital and nursing home patients, in particular.

Accordingly, the main objective of the invention is to provide amattress which is constructed to meet the needs of the art morecompletely than any known prior art proposal. In accordance with theinvention, a multisection mattress includes variable density componentsto support the head, shoulders, back, hips and heels with varyingdegrees of pressure on these parts of the body to promote maximumcomfort and to minimize the occurrence and severity of decubitus ulcersor bed sores. In furtherance of this objective, the mattress is employedin conjunction with and above a base which is additionally padded withfoam and the base is constructed in sections so as to be compatible withstandard articulated hospital type beds. The base may be one piece orcontinuous for use upon a conventional home bed.

Other features and advantages of the invention will become apparentduring the course of the following detailed description, and among thesefeatures are the economy of construction of the mattress and base,comparable to the cost of a good-quality hospital mattress and thedurability of the composite mattress and foundation which will last manyyears beyond the life of a conventional high quality hospital mattress.

BRIEF DESCRIPTION OF DRAWING FIGURES FIG. 1 is an exploded perspectiveview of a mattress and foundation therefor embodying the invention shownin association with a conventional hospital bed.

FIG. 2 is an enlarged longitudinal vertical section through the mattressand foundation taken on line 2-2 of FIG. 1.

FIG. 3 is a greatly enlarged fragmentary vertical section through themattress and foundation taken on the plane of FIG. 2.

FIGS. 4 and 5 are diagrammatic perspective views showing a comparison ofthe invention and the prior art.

DETAILED DESCRIPTION Referring to the drawings in detail wherein likenu-. merals designate like parts, the numeral designates a sectionalvariable density mattress inits entirety having a suitable fabricenvelope or cover 11. This mattress embodies a head support block orslab 12 of an open cell compressible foamplastic, such as foampolyurethane. In a typical embodiment, the head slab 12 is 36 incheswide by 12 inches long and 6 inches thick. While these dimensions arenot extremely critical, they are the most desirable dimensions. However,they may be varied in some cases. The preferred density of the foamemployed in the head slab 12 is approximately 1.75-1.85 lbs. per cubicfoot. The compressibility of the slab 12 to a thickness of about 4inches from the relaxed thickness of 6 inches can be expressed in termsof 24-30 lbs. loading on the entire upper surface of the slab.

The midsection of the mattress 10 which supports the shoulders and backof the user is composed of two superposed slabs 13 and 14, each of whichmeasures 36 inches wide by 44 inches long in the embodiment shown andeach of which is formed of open cell foam polyurethane or equivalentmaterial. The upper slab 13 is preferably 4 inches thick and the lowerslab is 2 inches thick. The density of the upper slab is from 2.2-2.4lbs. per cubic foot, and the density of the lower slab 14 is from1.75-1.85 lbs. per cubic foot. The compressibility of the upper slab 13in the same terms specified for the slab 13 is approximately 38-50 lbs.and for the lower slab 14 is approximately 24-30 lbs.

The mattress 10 further embodies a foot section or slab 15 of the samefoam plastic material measuring 36 inches wide by 24 inches long by 6inches thick. The particular foam used for the foot slab 15 preferablyhas a density of from 1.75-1.85 lbs. per cubic foot and acompressibility of 24-30 lbs. in the same terms expressed above for theother sections, namely the load necessary on the entire area of the slabto compress a 6 inch slab approximately 2 inches.

It may be seen that the composit mattress 10 contains regions or zoneswhich differ in density and compressibility and each zone is thereforecapable of exerting a specifically different pressure or resistance on aparticular part of the anatomy of the user. With the mattress positionedas in FIG. 2 and the head of the user adjacent to the slab 12, themattress will possess a first supporting capability. It may be seen thatif the mattress is reversed head-to-foot, or if it is inverted, a secondor new set of resistance values will be provided and this is sometimesbeneficial in relieving the monotony to the patient and in changing thedegrees of pressure on dif ferent parts of the body, which in turn canhelp relieve bed sores, fatigue and back ache. The mattress asconstructed, therefore, is very versatile.

In an alternate embodiment of the invention, a mattress was constructedin which the density of the foam employed in the head slab 12 isapproximately 1.6-1.75 lbs. per cubic foot. The compressibility of theslab 12 to a thickness of about 4 inches from the relaxed thickness of 6inches can be expressed in terms of a 23-29 lb. loading on the entireupper surface of the slab. The slab 12 is 36 inches wide and 18 incheslong.

The midsection of the mattress 10 which supports the shoulders and backof the user is composed of two superposed slabs 13 and 14, each of whichmeasures 36 inches wide by 33 inches long in the embodiment shown andeach of which is formed of open cell foam polyurethane or equivalentmaterial. The upper slab 13 is preferably 4 inches thick and the lowerslab is 2 inches thick. The density of the upper slab is from 2.6-2.75lbs. per cubic foot, and the density of the lower slab 14 is from 1.6-1.75 lbs. per cubic foot. The compressibility of the upper slab 13 in thesame terms specified for the slab 13 is, approximately 45-55 lbs.

6 inch slab approximately 2 inches.

It had been further determined that the head slab 12 may have a range ofdensities of from 1.4-1 .55 to 2-2.2 lbs. per cubic foot. The slab 12may have a rangeof compressibility in the same terms as expressed aboveof Invention Mattress- All Units on Invention Foundation:

used with a different type of foundation, such as a felt pad or somesort of box spring. In the total assembly, the foundation foam slabs orpads supplement and add to the net supportive effect of the mattress insuch a way as to produce the greatest comfort and beneficial effect forthe user or patient. The several sections of the foundation 16 arepreferably enclosed in individual covers 'or envelopes 34, 35, 36 and37, as shown.

To further emphasize the mertis of the invention in comparison toconventional extra firm solid mattresses. medium firm and regularhospital mattresses, a comparison chart is shown below. In this chart.the pressures exerted on different parts of the body are indisateqjn milime srw s x,

Head Shoulders Lumber Hips Heel Extra Firm Side 37 44 50 58 32 MediumFirm Side 31 36- 42 5] 26 ExtraFirm Side Reversed 34 39 54 Y 56 34 Headto Foot Medium Firm Side Reversed 34 37- 40 54 24 All units testedwithout foundation increased pressures by approximately 3 to 5 ,mm. ofHg. Extra Firm Solid Mattress- One Side 31 46 56 65 Repositioning andturning mattress reading remains the same. 1 Medium Firm Solid Mattress-One Side v 47 48 5 3 35 Repositioning and turning mattress readingremains the same. Regular Hospital Mattress- One Side 43 52 58 68 35Repositioning and turning mattressreading remains the same.

from 22-38 lbs per cubic foot. The range of the density 35 The figuresin the above chart are the results of a test of the upper slab 13 iffrom 2.2-2.4 to 2.8-2.9 lbs. per cubic foot. The range ofcompressibility for slab 13 is from 30-60 lbs.

The range of density and compressibility of slabs 14 using as a subjecta 6 foot tall, 185 pound person. Quite naturally, the test results willdiffer for each person and in this respect his to be understood thatthe. invention is capable of automatically compensating to produce and15 is the same-as the figure given for slab 12 above. the mostadvantageous supportive pressure on any per- An important feature of theinvention resides in the provision .of a foundation or base 16 to beused in conjunction with the mattress 10. This base 16, when used inconjunction with a hospital bed 17 such as the well- 5 known Joernshospitalbed, is formed in sections which correspond in length to thearticulated sections 18, 19 and 20 of the bed 17 and to the intermediatefixed section 21. correspondingly, the foundation 16 has sections 22,23, 24'and 25, as shown. These sections have the same width as themattress 10 and the same overall length, the individual foundationsections being formed lengthwise to fit the several sections of thehospital bed.

Each foundation section 22 through 25 includes a l and a compressibilityof 20-30 lbs. on the basis described for the mattress components. Thus,it may be seen that the foundation padding is somewhat softer and morereadily compressible than the softest sections of the mattress proper.However, when the mattress is placed upon the foundation 16 for use, thecomposite assembly which represents the total invention gives adifferent effect than would be achieved if the mattress alone were.uscqwitncu .Lhe..f9t1&12!i.%,9if were son or'body of sufficient adultsize to span the mattress.

The figures in the comparison chart demonstrate that the mattress, whenutilized properly with the foundation 16, exerts the minimum unitpressures on the various parts of the anatomy and these pressures aresignifi-v cantly lower than the corresponding pressures exerted by theconventional and hospital mattresses. The test results also show thatthe parts of the anatomy requiring the greatest degree of support,namely the back and hips, receive this support with the invention andthe 'parts'requiring lesser supporting pressure, namely the head andheels, are properly accommodated.

With reference to FIG. 4, aprior art solid-mattress such as a regularhospital mattress is illustrated and it will be observed how the body ofthe user depresses the prior art mattress unevenly due to the fact thatthe mattress is unable to compensate for the different weight regions ofthe body. FIG. 5, on the other hand, shows the invention with itsdifferent density and compressibility zones enabling the mattress andfoundation assembly to support the body without extreme deformation, theassembly automatically exerting the necessary unit pressures on thedifferent regions of the body with the necessary differential to alloweven support along the full length of the body and minimum mattresscompression or deformation.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to, without departing from the spirit of the invention or scopeof the subjoined claims.

I claim:

1. A mattress made of foam having three distinct sections, said distinctsections being integral and coextensive with each other, said foammaterial of the first zone having a first density and compressibilityfactor at 4 inches in the order of 22 to 30 lbs. per cubic foot, saidsecond zone being adjacent to said first zone and having a seconddensity and second compressibility factor, said second zone having afirst and second portion, said first portion having a compressibilityfactor at4inches in the order of 37 to 60 lbs. per cubic foot, and saidthird zone adjacent to said second zone and having a third density andcompressibility factor at 4 inches i t 1 the order of 2 2 to 30 lbs. percubic foot, and said second portion of said second zone having acompressibility factor at 4 inches in the order of 22 to 30 lbs. percubic foot.

2. The mattress of claim 1, in which the material of first zone andthird zone have identical density and compressibility factorsdifferentfro m that of the 5&

ond zone in the order of 1.4-2.2 lbs. per cubic foot said density ofsaid first portion of said second zone being in the order of 185-29 lbs.per cubic foot, whereby the various densities and compressibilityfactors of said foam cooperate to form a mattress having therapeuticsupport qualities to the users thereof.

3. A mattress made of foam having three distinct sections, said distinctsections being integral and coextensive with each other, said foammaterial of the first zone having a first density and compressibilityfactor at 4 inches in the order of 23 to 30 lbs. per cubic foot, saidsecond zone being adjacent to said first zone and having a seconddensity and second compressibility factor, said second zone having afirst and second portion, said first portion having a compressibilityfactor at 4 inches in the order of 38 to 55 lbs. per cubic foot, andsaid third zone adjacent to said second zone and having a third densityand compressibility factor at 4 inches in the order of 24 to 30 lbs. percubic foot, and said second portion of said second zone having acompressibility factor at 4 inches in the order of 23 to 30 lbs. percubic foot.

4. The mattress of claim 3, in which the material of first zone andthird zone have identical density and compressibility factors differentfrom that of the second zone in the order of 1.6-1.85 lbs. per cubicfoot said density of said first portion of said second zone being in theorder of 22-275 lbs. per cubic foot, whereby the various densities andcompressibility factors of said foam cooperate to form a mattress havingtherapeutic support qualities to the users thereof.

5. A mattress made of foam having three distinct sec tions, saiddistinct sections being integral and coextensive with each other, saidfoam material of the first zone having a first density andcompressibility factor at 4 inches in the order of 23 to 29 lbs. percubic foot, said second zone being adjacent to said first zone andhaving a second density and second compressibility factor, said secondzone having a first and second portion said first portion having acompressibility factor at 4 inches in the order of 45 to 55 lbs. percubic foot, and said third zone adjacent to said second zone and havinga third density and compressibility factor at 4 inches in the order of23 to 29 lbs. per cubic foot, said second portion of said second zonehaving a compressibility factor at 4 in the order of 23 to 29 lbs. percubic foot, and said material of first zone and third zone havingidentical density and compressibility factors different from that of thesecond zone in the order of L6 to 1.75

lbs. per cubic foot, said density of said first portion of said secondzone being in the order of 2.6 to 2.75 lbs. per cubic foot, whereby thevarious densities and compressibility factors of said foam cooperate toform a mattress having thereapeutic support qualities to the usersthereof.

1. A mattress made of foam having three distinct sections, said distinctsections being integral and coextensive with each other, said foammaterial of the first zone having a first density and compressibilityfactor at 4 inches in the order of 22 to 30 lbs. per cubic foot, saidsecond zone being adjacent to said first zone and having a seconddensity and second compressibility factor, said second zone having afirst and second portion, said first portion having a compressibilityfactor at 4 inches in the order of 37 to 60 lbs. per cubic foot, andsaid third zone adjacent to said second zone and having a third densityand compressibility factor at 4 inches in the order of 22 to 30 lbs. percubic foot, and said second portion of said second zone having acompressibility factor at 4 inches in the order of 22 to 30 lbs. percubic foot.
 2. The mattress of claim 1, in which the material of firstzone and third zone have identical density and compressibility factorsdifferent from that of the second zone in the order of 1.4-2.2 lbs. percubic foot said density of said first portion of said second zone beingin the order of 1.85-2.9 lbs. per cubic foot, whereby the variousdensities and compressibility factors of said foam cooperate to form amattress having therapeutic supPort qualities to the users thereof.
 3. Amattress made of foam having three distinct sections, said distinctsections being integral and coextensive with each other, said foammaterial of the first zone having a first density and compressibilityfactor at 4 inches in the order of 23 to 30 lbs. per cubic foot, saidsecond zone being adjacent to said first zone and having a seconddensity and second compressibility factor, said second zone having afirst and second portion, said first portion having a compressibilityfactor at 4 inches in the order of 38 to 55 lbs. per cubic foot, andsaid third zone adjacent to said second zone and having a third densityand compressibility factor at 4 inches in the order of 24 to 30 lbs. percubic foot, and said second portion of said second zone having acompressibility factor at 4 inches in the order of 23 to 30 lbs. percubic foot.
 4. The mattress of claim 3, in which the material of firstzone and third zone have identical density and compressibility factorsdifferent from that of the second zone in the order of 1.6-1.85 lbs. percubic foot said density of said first portion of said second zone beingin the order of 2.2-2.75 lbs. per cubic foot, whereby the variousdensities and compressibility factors of said foam cooperate to form amattress having therapeutic support qualities to the users thereof.
 5. Amattress made of foam having three distinct sections, said distinctsections being integral and coextensive with each other, said foammaterial of the first zone having a first density and compressibilityfactor at 4 inches in the order of 23 to 29 lbs. per cubic foot, saidsecond zone being adjacent to said first zone and having a seconddensity and second compressibility factor, said second zone having afirst and second portion said first portion having a compressibilityfactor at 4 inches in the order of 45 to 55 lbs. per cubic foot, andsaid third zone adjacent to said second zone and having a third densityand compressibility factor at 4 inches in the order of 23 to 29 lbs. percubic foot, said second portion of said second zone having acompressibility factor at 4 in the order of 23 to 29 lbs. per cubicfoot, and said material of first zone and third zone having identicaldensity and compressibility factors different from that of the secondzone in the order of 1.6 to 1.75 lbs. per cubic foot, said density ofsaid first portion of said second zone being in the order of 2.6 to 2.75lbs. per cubic foot, whereby the various densities and compressibilityfactors of said foam cooperate to form a mattress having thereapeuticsupport qualities to the users thereof.